Write Up:

A traffic incident is an unplanned event that blocks travel lanes and temporarily reduces the number of vehicles that can travel on the road. The speed of incident clearance is essential to the highway system returning to normal conditions. Responding to and quickly addressing the incident (crashes, debris and stalled vehicles) improves system performance.

St. Louis recorded 3,185 incidents in the third quarter of 2020. The average time to clear traffic incidents was 27.3 minutes, an increase of 9.2% from the third quarter of 2019.

Kansas City recorded 1,960 incidents in the third quarter of 2020. The average time to clear traffic incidents was 24.4 minutes, an increase of 8.0% from the third quarter of 2019.

Springfield recorded 436 incidents in the third quarter of 2020. The average time to clear traffic incidents was 32.2 minutes, a decrease of 19.3% from the third quarter of 2019.

Rural counties of I-70 between mile marker 28 (Oak Grove) to MM 203 (Foristell) recorded 79 incidents in the third quarter of 2020. The average time to clear traffic incidents was 79.3 minutes, an increase of 43.1% from the third quarter of 2019.

Rural counties of I-44 between MM 0 (Oklahoma) to MM 69 (Springfield) and MM 91 (Strafford) to MM 224 (Sullivan) recorded 94 incidents in the third quarter of 2020. The average time to clear traffic incidents was 64.8 minutes, an increase of 48.3% from the third quarter of 2019.

Overall, there were 616 or 9.6% fewer traffic related incidents during the third quarter of 2020 compared to same time period in 2019. As before, much of this can be attributed to the reduced traffic volumes during the COVID-19 pandemic. Clearance times, however, went up in all areas except for the Springfield urban area. This can be partially attributed to an overall increase of 28.5% in the major category traffic incidents in those areas, which follows the trend of more severe traffic incidents due to excessive vehicle speeds and inattention. Another contributing factor could be the reduction in Motorist Assist hours worked as a result of the Shared Work Program. As MoDOT strives  to clear incidents quickly with Traffic Incident Management, one thing to note is there are times where it makes sense to push vehicles and tractor trailers to the shoulder to do the recovery at a later time when traffic volumes are significantly decreased to reduce the impact and delay to motorists and also improve the safety for employees and partners. As such, some of the incidents in the major category are for the recovery efforts and not tied directly to when the incident actually occurred.

Purpose of the Measure:

This measure is used to determine the trends in incident clearance on the state highway system.

Measurement and Data Collection:

Advanced transportation management systems are used by the St. Louis, Kansas City and Springfield traffic management centers to record incident start time and the time when all lanes are declared cleared. Traffic incidents can be divided into three general classes of duration set forth by the Manual on Uniform Traffic Control Devices that include minor, intermediate and major incidents. Each class has unique traffic control characteristics and needs.

This target is established by projecting a 10% improvement over a five-year average.